Email · guide
How long does domain warmup take? 3 to 8 weeks. Here is why.
Inbox providers trust domains, not intentions. A new domain has no history, so its reputation is built slowly, by real sends. This guide covers the warmup clock, the three DNS records that gate everything, and the SES sandbox.
The clocks
DNS records. SPF, DKIM, and DMARC entries, plus rDNS on your sending IPs. Quick to set, easy to get subtly wrong.
Warmup. Volume ramps from tens of messages a day to your real volume, with engagement watched the whole way. Rushing it burns the domain you are trying to build.
SES production access. Amazon reviews your request to leave the sandbox. Denials often come without a stated reason or an appeal path.
What the three records do
- SPF lists the servers allowed to send for your domain. One TXT record; more than 10 DNS lookups inside it and it silently fails.
- DKIM signs each message so receivers can verify it was not altered and came from you.
- DMARC tells receivers what to do when SPF or DKIM fails, and where to send reports. Start at p=none, read the reports, then tighten.
Where Hail fits
Hail gives agents and backends real inboxes with deliverability tracking built in: delivery, opens, bounces, and complaints per domain, with SPF, DKIM, and DMARC status checked continuously. The deliverability checker is free for any domain, no signup.
Questions
How long does email domain warmup take?
3 to 8 weeks for a new domain, ramping volume gradually while inbox providers build a reputation for it. Sending full volume on day one gets a new domain filtered.
Do I need SPF, DKIM, and DMARC?
Yes, all three. SPF lists who may send for the domain, DKIM signs each message, and DMARC tells receivers what to do when either fails. Missing records are the fastest route to the spam folder.
Why was my AWS SES production access denied?
SES keeps new accounts in a sandbox until you justify your sending. Denials frequently arrive without a specific reason or a clear appeal path, and repeated requests can be rejected the same way.
How do I know if my email lands in spam?
Track delivery, opens, bounces, and complaints per domain, and check your records. Hail's free deliverability checker inspects SPF, DKIM, and DMARC for any domain.
Timelines reflect published provider documentation and common practice as of August 2026; they change. Verify against your provider's current docs.